Muffler



Oct. 24, 1944. v. E. SPROUSE MUFFLER Filed Nov. 22, 1945 INVEHTOR. Verner E. p w

Patented Get. 24, 1944 UNITED STATES PATENT OFFICE MUFFLER Verner E. Sprouse, Columbus, Ind. Application November 22, 1943, Serial No. 511,219

6 Claims.

This invention relates to a structure for a transfer of heat from an engine exhaust mufiler and has for a primary object the provision of a structure which will not only be highly efficient in the transfer of heat but which will also afford the maximum possible safety against entrance of exhaust gases into the heated member.

Another primary object of the invention is to provide an exceedingly simple structure which may permit the detachment of the heated member from the muiller for inspection of the primary heat transfer surfaces as a check against exhaust gas leakages. A further primary object of the invention is to provide a simple and durable structure.

These and many other objects and advantages of the invention will become apparent to those versed in the art in the following description of one particular form of the invention as illustrated in the accompanying drawing, in which Fig. 1 is a view principally in central, vertical, longitudinal section through the structure embodying the invention; and I Fig. 2, a view in end elevation and partial section.

Like characters of reference indicate like parts in the two views in the drawing.

The form of the invention herein shown and described is that particularly adapted to an airplane wherein there are two exhaust lines leading from the engine to connect with the two intake pipes I and I I of the mufiier, generally designated by the numeral I2. The mufiler I2, in the form herein shown, is cylindrical in shape having an outer wall formed of metal inclosed at its ends by the heads I3 and I4. The muffler is provided with a transverse floor I5 thereacross removed from a diametrical plane. Both of the intake pipes I0 and I I pass through the cylindrical wall of the muffler with a gas tight joint there around and continue on through the floor l5 to open in the chamber therebelow by their ends. Both pipes I0 and I I are provided with a plurality of ports or discharge openings I6 in those lengths between the cylindrical wall of the muffler and the upper side of the floor [5.

The floor I5 is provided with a plurality of openings I I, herein shown as two in number, and spaced between the two pipes I0 and II. The floor I5 is flanged upwardly around the openings I1 to form in eifect in each instance an upwardly directed nipple. The chamber formed above the floor I5 has a central discharge pipe I8 leading therefrom down through the chamber below the floor I5 to open externally of the wall of the mufller I2, the pipe I8 being sealed around its J'unction'with the floor I5 and the outer wall of the muilier whereby no communication may be had from the chamber below the floor I5 into the pipe I8 except as may be had directly through the opening l1, and around into the upper end of the pipe l8.

The chamber above the floor I5 is reduced in volume by means of a box I9 having a lower floor 20 and end walls 2| and 22 positioned between the pipes I0 and II and attached to the outer wall of the mufiler I2 to have the floor 2|] disposed above the diametrical plane in parallel relation to the floor I5 and spaced therefrom. To prevent drumming and also to aid in sound absorption, a tube 23, open at both ends, is carried through the floor 20 and held thereby, the major portion of the tube 23 being within the box I9. This tube 23 is axially centered with the axis of the pipe I 8. The length of the floor 20, that is, longitudinally of the mufiler I2, is sufficient to extend at least to be in line with the outer marginal portions of the holes I1.

In that particular form of a mufller, it is to be noted that the incoming exhaust gases discharge 1 primarily from the ends of the pipes I0 and II into the chamber below the floor I5 to impinge against the lower curved wall of the muiiler shell. In respect to directions indicated, that is, when reference is made to the chambers above and be-- low the floor I5, it is tobe understood that such directions are relative since the mufiler may be used in any position. Pressure in the chamber below the floor I5 is relieved by escape of gases upwardlythrough the hole I I and around and down again through the pipe I8, much of the heat, however; having been previously transferred from the gases to the wall of the mufller.

A heat unit, generally designated by the numeral 24, is constructed to have a top inclosing wall 25 arcuate in shape with a curvature permitting it to fit intimately around the under side of the shell of the mu fller I2. Preferably this wall 25 is made out of a material such as copper or aluminum, so as to be of high heat conductivity.. The side edge portions of this wall 25 are united in a gas tight manner with an inclosing under wall 26 which has a lower curved portion extending therefrom by sides that continue beyond the marginal portions of the wall 25 to terminate in downwardly turned flanges 21 and 28 respectively. While both floors 25 and 26 are curved, the side walls of the floor 26 are sufficiently long to permit the desired spacing between those two floors whereby heat conducting baffles 29 may be mounted and secured therebetween. A plurality of these baffles 29 is employed, four in the present instance, and each of these bafiles is provided with a plurality of holes therethrough whereby any medium, such as air, entering the intake pipe in an end inclosure of the chamber 24, may travel through those baffie holes from the intake end to the discharge end of the chamber. While the discharge from the chamber may be in any desired direction, it is herein shown as being provided through a pipe 3| that is downturned from an end portion of the floor 26. About the holes in each of the baffles 29, the metal from which the baflle plate is made is preferably flanged to form projecting nipples, herein shown as directed against the current of air flowing through the holes.

The chamber 24 is provided with a tube 32 extending therethrough and gas sealed around its junction with each of the walls 25 and 26. This tube 32 is axially aligned with the pipe l8 and an exhaust discharge pipe 33 is telescoped through the tube 32 to have an end extending into the muffler pipe I8. To aid in as sembly, the lower end of the pipe [8 is formed to project slightly outside of the wall of the mufiler l2 and the tube 32 is offset or counterbored by its upper end to receive therein this lower end of the pipe l8 whereby the chamber 24 is centered and positioned along the muffler l2.

Extending longitudinally along each side of the wall of the muffler l2 and on the outside face thereof is an attaching member 34 and 35 respectively having its lower edge turned around and upwardly. These members 34 and 35 are located along the sides of the muffler l2 to be immediately above the terminal flange ends of the upwardly extending sides of the floor 26. A slide 36, generally C-shaped in cross-section, is employed to interengage over the upturned end of the member 34 and the downwardly turned edge of' the side wall presented thereunder by the chamber 24. Engagement between those two terminal edges is had by the slide 36 by starting the slide member from one end of those members and pushing it therealong. As indicated in Fig. 2, the upper downturned portion of the slide 36 engages over the top edge of the upturned edge portion of the member 34 while the lower upturned portion of the slide 36 engages around under the downturned portion of the side wall of the floor 26. In the same manner, a slide 31 interengages the upwardly and downwardly extending edge portions respectively of the upper member 35 and the side wall of the floor 26. These members are so proportioned that the floor 25 will be held firmly against the wall of the muffler l2 and yet by removing the slides 36 and 31, the chamber 24 is released from the muffler l2 whereby the wall of the muiiier may be checked to determine whether or not that wall has become dangerously burned by the heat of the exhaust gases.

Heat delivered to the wall of the muffler l2 will be radiated and conducted to the floor 25 of the chamber 24 without any appreciable heat loss since the two walls are in intimate contact with each other. The floor 25 is of a greater heat conductivity than that of the wall of the muffler l2 and hence will rapidly conduct the heat away from that mufiier wall not only to radiate the heat within the chamber 24 but also to have the heat conducted through the baiile plates 29 to further distribute the heat for quick transfer of the flow of air going through the chamber 24,

through the holes of the baffles 29 and out the discharge pipe 3|. Of course, heat will also be transferred from the pipe 33 through the tube 32 to radiate and be conducted into the chamber 24. As above indicated, the mufller I2 is so designed as to have the highest temperature part on that side against which the chamber 24 is attached. The use of the holes IS in the intake pipes l0 and II is primarily to break up sound waves and incidentally to help reduce back pressure.

While I have herein shown and described my invention in the one particular form, it is obvious that structural variations may be employed without departing from the spirit of the invention and I therefore do not desire to be limited to that precise form beyond the limitations as may be imposed by the following claims.

I claim:

1. An engine exhaust gas mufiier adapted for heat exchange use comprising in combination a tubular housing shell; end heads closing the shell; a fioor within the shell extending longitudinally thereof to divide the shell into two chambers; an inlet tube entering the shell toward one end thereof and passing through one of said chambers and said floor to open into the other chamber; a second inlet tube entering the shell toward the other shell end and passing through the same chamber to open into said other chamber; said floor having at least one opening therethrough to afford communication between both of said chambers; an exhaust gas tube positioned substantially centrally of said shell to extend from an open end in said first chamber across said other chamber and open outside of said shell.

2. An engine exhaust gas muilier adapted for heat exchange use comprising in combination a tubular housing shell; end heads closing the shell; a floor within the shell extending longitudinally thereof to divide the shell into two chambers; an inlet tube entering the shell towards one end thereof and passing through one of said chambers and said floor to open into the other chamber; a second inlet tube entering the shell toward the other shell end and passing through the same chamber to open into said other chamber; said floor having at least one opening therethrough to afford communication between both of said chambers; an exhaust gas tube positioned substantially centrally of said shell to extend from an open end in said first chamber across said other chamber and open outside of said shell; both of said inlet tubes being foraminous within said shell.

3. An engine exhaust gas muiller adapted for heat exchange use comprising in combination a tubular housing shell; end heads closing the shell; a floor Within the shell extending longitudinally thereof to divide the shell into two chambers; an inlet tube entering the shell toward one end thereof and passing through one of said chambers and said floor to open into the other chamber; a second inlet tube entering the shell toward the other shell end and passing through the same chamber to open into said other chamber; said floor having at least one opening therethrough to afford communication between both of said chambers; an exhaust gas tube positioned substantially centrally of said shell to extend from an open end in said first chamber across said other chamber and open outside of said shell; both of said inlet tubes being foraminous within said 'shell; said floor opening having a marginal flange turned into said first chamber; and said exhaust tube having an end portion extending beyond said floor into said first chamber.

. 4. An engine exhaust gas mufller adapted for heat exchange use comprising in combination a tubular housing shell; end heads closing the shell; 2, floor within the shell extending longitudinally thereof to divide the shell into two chambers; an inlet tube entering the shell toward one end thereof and passing through one of said chambers and said floor to open into the other chamber; a second inlet tube entering the shell toward the other shell end and passing through the same chamber to open into said other chamber; said floor having at least one opening therethrough to afford communication between both of said chambers; an exhaust gas tube positioned substantially centrally of said shell to extend from an open end in said first chamber across said other chamber and open outside of said shell; both of said inlet tubes being foraminous with said shell; wall means in said first chamber defining an auxiliary chamber therewithin against said shell over and spaced from said exhaust gas tube opening within the shell chamber; and an opening into said auxiliary chamber axial- 1y aligned and over the opening of said exhaust gas tube.

5. An engine exhaust gas mufiler adapted for heat exchange use comprising in combination a tubular housing shell; end heads closing the shell; a floor Within the shell extending longitudinally therof to divide the shell into two chambers; an inlet tube entering the shell toward one end thereof and passing through one of said chambers and said floor to open into the other chamber; a second inlet tube entering the shell toward the other shell end and passing through the same chamber to open into said other chamber; said floor having at least one opening therethrough to afford communication between both of said chambers; an exhaust gas tube positioned substantially centrally of said shell to extend from an open end in said first chamber across said other chamber and open outside of said shell; both of said inlet tubes being foraminous with said shell; wall means in said first chamber defining an auxiliary chamber therewithin against said shell over and spaced from said exhaust gas tube opening within the shell chamber; and an opening into said auxiliary chamber axially aligned and over the opening of said exhaust gas tube; and a tube extending through a wall of said auxiliary chamber, said auxiliary chamber opening being through said tube.

,6. An engine exhaust gas mufller adapted for heat exchange use comprising in combination a tubular housing shell; end heads closing the shell; a floor within the shell extending longitudinally thereof to divide the shell into two chambers; an inlet tube entering the shell toward one end thereof and passing through one of said chambers and said floor to open into the other chamber; a second inlet tube entering the shell toward the other shell end and passing through the same chamber to open into said other chamber; said floor having at least one opening therethrough to afford communication between both of said chambers; an exhaust gas tube positioned substantially centrally of said shell to extend from an open end in said first chamber across said other chamber and open outside of said shell; and flange means carried along and on opposite sides of said shell to support and retain a heat exchanger unit thereagainst.

VERNER E. SPROUSE. 

